The New Arrowverse "Elseworlds" Poster Teases A Superhero Switcheroo That No One Could See Coming — PHOTO

Katie Yu/The CW

The annual crossover event of the Arrowverse is coming up in December, and it looks like it might just be the most shocking yet. This year, in a three episode arc spanning Arrow, The Flash, and Supergirl, all of The CW's favorite superheroes will meet up for "Elseworlds." The title of the crossover already revealed that fans would be entering a sort of alternate reality, but a new Arrowverse "Elseworlds" poster really hits that home, as it looks like Oliver Queen is going to be Barry Allen... and Barry Allen is Oliver Queen.

Arrow star Stephen Amell tweeted the official artwork from the upcoming Arrowverse crossover on Oct. 16. At a quick glance, it looks like a normal superhero promo shot. But a closer look shows that the man wearing The Flash's supersuit is actually Amell, and the Arrow behind him is actually Flash star Grant Gustin. "Destiny Will Be Rewritten," reads the tagline at the top of the poster.

So, Barry Allen is the Green Arrow and Oliver Queen is The Flash? Well, not quite. In his tweet, Amell seemed to confirm that he'll actually be playing Barry Allen, writing, "My name is Barry Allen and I am the fastest man alive." So far, Elseworlds, which premieres Dec. 9 on The CW, is going to be a trip.

In a follow-up tweet, Amell wanted to squash the naysayers who doubted the authenticity of the photo, and confirmed that indeed, he is the one in the red suit. “This is real, btw. I’m in the Flash suit while I type this,” he wrote. Still doubting him? Well, over on his Instagram story, there’s even more proof (it’s his foot in The Flash costume, stuck out for the world to see).

@stephenamell

Besides being super trippy, and confusing at first, this new image may not actually be all that shocking if you think about it. The title for the three-night event is “Elseworlds” and DC comic fans might find that name familiar. It was a series of comics from DC that basically told a ton of "what if" scenarios starring everyone's favorites superheroes.

Basically, there's regular continuity in comics which is the way we know the iconic heroes as they are. Superman came from Krypton as a baby and lives his life as Clark Kent among humans; Batman is an orphan from Gotham and fights crime with gadgets in his supersuit; etc. In Elseworlds, however, some events were changed that altered the superheroes' very identities, creating an entirely new cannon. So this Freaky Friday moment between Amell’s and Gustin’s characters actually makes a lot of sense. But just because it's logical doesn't mean it will make the image any less strange for fans.

Filming began on Oct. 9, and this new Superman suit is not the only noteworthy costume fans have seen from the upcoming crossover. Gustin posted a photo of Amell and him, looking on at Tyler Hoechlin (aka Superman) in a black suit. There was still the Kryptonian symbol on his chest (the “S”), but it was all black. This is just like the suit he wore in TheDeath of Superman comics after he’s brought back after falling to Doomsday. Another photo from Amell shows Gustin and him in matching outfits that are basically bad-boy-motorcyclists-meet-cowboy.

Where is Supergirl in all this? Will there even be a Supergirl in "Elseworlds," or will Kara Danvers be someone else entirely? And how does Ruby Rose's Batwoman fit into all of this? There are still a lot of questions, and Amell’s and Gustin’s posts aren’t really giving fans the answers they're hoping for, but they sure are giving us things to talk about.